too much disk activity?

I just installed Winxp and I am noticing after about 10 minutes away from the computer my hard drive just starts running and running. I turned off the screen saver and it still does this. Could someone tell me if this is a normal occurance and/or if can I stop it from happening?

I too encounter this kind of prob... but slightly different from u. It occurs especially during boot up( after the XP logon screen) , the HD will blink unexpectedly though all appz has loaded on the taskbar and i've even disable the antivirus but the prob still took place. Any idea to solve this prob...